Current projector display systems use cathode ray tubes (CRTs) or spatial light modulators such as transmissive liquid crystal display (LCD) panels, liquid crystal on Silicon (LCoS) devices, or micro-electro-mechanical system (MEMS) mirror arrays. Single-panel multicolor displays that use CRTs, LCD or LCoS are not efficient due to the limited numerical aperture of the devices. Triple panel multicolor displays that use CRTs, LCD or LCoS are expensive.
MEMS-based projector display systems include display devices with a reflective segment for each pixel to redirect light incident on each reflective segment as needed for the projected image. MEMS-based displays have better contrast than the CRT, LCD, and LCoS based displays, however they are expensive because the fabrication process requires low-yield process steps in which a sacrificial layer is deposited and subsequently etched out below the reflective surface. One MEMS-based device is the Texas Instruments digital light processing chip, which uses electrostatic attraction to bend a deflectable reflecting flap to redirect incident light as described in U.S. Pat. No. 4,615,595 of Hornbeck entitled Frame Addressed Spatial Light Modulator, issued on Oct. 7, 1986.
A market demand exists for efficient, inexpensive and high contrast projector display devices for use in color display systems.